Class: PassiveColumns::Loader

Inherits:
Object
  • Object
show all
Defined in:
lib/passive_columns/loader.rb

Overview

Loader is a class helper that loads a column value from the database if it is not loaded yet.

Instance Attribute Summary collapse

Instance Method Summary collapse

Constructor Details

#initialize(model, passive_columns) ⇒ Loader

Returns a new instance of Loader.

Parameters:

  • model (ActiveRecord::Base)
  • passive_columns (Array<Symbol>) 


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# File 'lib/passive_columns/loader.rb', line 10

def initialize(model, passive_columns)
  @model = model
  @passive_columns = passive_columns
end

Instance Attribute Details

#model ⇒ Object (readonly)

Returns the value of attribute model.



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# File 'lib/passive_columns/loader.rb', line 6

def model
  @model
end

#passive_columns ⇒ Object (readonly)

Returns the value of attribute passive_columns.



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# File 'lib/passive_columns/loader.rb', line 6

def passive_columns
  @passive_columns
end

Instance Method Details

#load(column, force: false) ⇒ any

Parameters:

  • column (Symbol, String)
  • force (Boolean) (defaults to: false)

Returns:

  • (any) 


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# File 'lib/passive_columns/loader.rb', line 18

def load(column, force: false)
  return yield if block_given?

  model.send(column)
rescue ActiveModel::MissingAttributeError
  allowed_columns = (force ? [column] : passive_columns).map(&:to_s)
  raise if allowed_columns.exclude?(column.to_s) || identity_constraints.value?(nil)

  value = pick_value(column)
  model[column] = value
  model.send(:clear_attribute_change, column)
  model[column]
end